The present invention is directed to a cutter bit or chisel bit, hereinafter a cutter bit. The bit has a leading or working end and a trailing end. The trailing end is arranged to be inserted into a tool chuck, such as in a hammerdrill and the like. The leading end is a cutting member. A shank extends between the leading and trailing ends. The shank has a first axially extending section of constant cross section extending from the grailing end and a second axially extending section of diminishing cross-section extending from the first section to the leading end.
Generally with chisel cutters, the shank between the trailingend and the leading end, that is the bit end, is cylindridal. A cutter is disclosed in DE-OS 1 073 410, where the shank tapers conically toward the leading end.
The disadvantage in both instances is that in shock wave-like loading, the energy expended is not optimally utilized and, therefore, the output at the cutter tip is not completely attained.